CLEARWATER — City Council members on Wednesday unanimously agreed to a revamped agreement that could allow Clearwater Marine Aquarium to build a $160 million attraction downtown.

After scrutiny by Mayor George Cretekos and other city council members earlier this week, the aquarium renegotiated its deal with the city, significantly increasing its offer for a 60-year lease on the current city hall site.

Under the revised deal, the aquarium would add interest to the $7.5 million it already planned to pay the city for the construction of a new city hall. Once the new city hall building is paid off, the aquarium would pay $250,000 a year through the end of the 60-year lease, rather than its previous offer of $150,000.

The new agreement contains revised language explicitly stating that the city will not use any money from its general fund to build the new facility. The agreement also ensures that the city can review the aquarium’s financing before vacating city hall.

A citywide referendum on the aquarium lease is scheduled for Nov. 5.

The agreement drew both praise and criticism from city residents and business leaders at Wednesday night’s City Council meeting.

“I don’t think there’s another opportunity probably in my lifetime that’s going to have this kind of impact,” City Council member Jay Polglaze said.

Cretekos said the aquarium had satisfied his earlier concerns that the city was not receiving enough revenue to cover costs of infrastructure improvements needed to accommodate the aquarium.

Joseph Corvino and several other city residents who spoke before the vote criticized the deal.

“They’re a private business. Go buy a piece of land, build your aquarium and reap the rewards. Don’t put it here,” Corvino said, voicing concerns about the attraction’s long-term ability to pay down its debts.

The agreement approved Wednesday is preliminary. If residents approve the referendum, the city has the option to offer the lease but isn’t obligated to do so.

But the tentative terms will guide voters in their decision about whether to lease to the aquarium the prime downtown parcel for the proposed 200,000-square foot attraction.

The city ordered an appraisal this spring that estimated the City Hall property’s market value at $6.6 million. The Pinellas County Property Appraiser set the property’s fair market value at almost $16.5 million in 2012, though Vice Mayor Paul Gibson said that number doesn’t accurately reflect what a buyer would actually pay.

Under the agreement, the aquarium would use a 50-cent surcharge on tickets to pay for a new city hall, which city staff estimates would cost $7.5 million. The aquarium also would pay $250,000 in annual rent for the duration of the lease.

The aquarium would pay for City Hall’s demolition, though the city would be responsible for taking care of any asbestos removal in the aging building.

The aquarium is required to have all funds in place by Aug. 1, 2016. Should the aquarium default on its loans, the city would not be liable and creditors would be required to either take over management of the property or raze the building and return the property to the city, city attorney Pam Akin said.

The agreement also calls for the construction of a new parking garage. Aquarium officials estimate the attraction and its movie star dolphin, Winter, will draw at least 1 million people downtown each year. Who would build and maintain the garage remains to be hashed out.

The city would also agree to pay for road work linking Pierce Street with Drew and Cleveland Streets.

Business leaders like Clearwater Regional Chamber of Commerce Chairman Nick DiCeglie praised the city and aquarium officials for reaching a deal.

“It’s really refreshing to see both parties come to a really fair agreement for the city,” said DiCeglie.

Aquarium director David Yates said before the meeting he expects voters to embrace what he sees as a generous deal with the city.

“We don’t own it. We only get use it for 60 years. As far as a deal for the voters, I don’t see how you get any stronger than that,” Yates said.

Former Mayor Frank Hibbard, who is on the aquarium board, said he would work to continue to answer questions from critics and build support ahead of the referendum.

“I want to assure you we will continue to work with them to quell their fears,” he said.